Dr. Shima D. Anwar, MD PHD

• The bladder, which stores urine.
• The urinary sphincters, which are muscles around the opening of the bladder that hold urine in.
• The urethra, which is the tube where urine flows out of the body.

Urodynamics tests are normally performed together as one series, but depending on patients' symptoms, only one or some of them may be necessary. The most common tests are:

• Cystometrogram, which measures the amount of urine the bladder can store and how full it is before someone has the urge to urinate. Doctors may order this test if she suspects their patient has a weak bladder.
• Pressure flow study, which measures the pressure in the bladder while urinating. This test helps locate a blockage in the bladder.
• Uroflowmetry, which measures how much and how fast urine flows out of the body. This test is usually recommended when patients have difficulty urinating or they have a slow stream.
• Urethral sphincter electromyography, which measures how strong the muscles and nerves in the bladder and sphincters are. Doctors may request this test if the problem they are experiencing is linked to muscle or nerve damage in the lower urinary tract.
• Urethral pressure profile, which measures the pressure along the urethra while the bladder is gradually filled with fluid. Low pressure could mean someone has a weak urethra, a contributing factor to urinary incontinence (loss of bladder control).

For a few hours following a urodynamics study, patients will likely feel some soreness or discomfort. It is recommended to drink at least one glass of water every half hour for two hours to relieve these symptoms. Holding a warm, moistened washcloth over the area where discomfort is felt or taking a warm bath may also help. Results for cystrometrograms and uroflowmetry are typically available immediately after the test, but results for the other tests may take a few days. When doctors have reviewed a patient's test results, he or she will discuss them with the patient, along with any treatments the patient may need.